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Radiitip ai

killer that.

ee

* How much radioactive
ust is formed in an
hydrogen bomb explo-
on, and for how long
és ls it dangerous?
) RING the first 36 hours the
“ ate exploded by the U.S.
hay Ini on March 1, 1954, would
ve peo inated an area the
miles Wales, about 7,000 square
i With “fission products”—
ia eve ashes of the plu-
™M explosion,
€tybody in the area would
Be died unless they were in
i Shelters although this was
Sly far out of range of the
Such an area could not
din for many months.
Sion | POmDS, in addition to fis-
as also make a form
loactive carbon known as
N14, from atmospheric _ni-

have

de live

verttbon 14 takes nearly 6,000
anq -.° lose half its activity,
Po *emains in the atmosphere.
there Practical purposes it is
Wher.’ keeps, and each bomb,
Deaga  XPloded in war or

a Makes a little more of it:
a shot 2 long-term rather than
dange ‘term menace. It is not
be go US at present, but will
On, »f nuclear explosions go
thous Bh have already been
19g5 °* Nuclear explosions since

What is the safety level

thou’ dy does some harm,
Stem, low certain levels this
Who wor, Slight to matter. Those
Stanoag «With radioactive sub-
Posture 2 hospitals avoid ex-
Pramer er ever possible.
bout ly, We do not know much
radiation ® biolegical effects of
ly Not 47°92 We should certain-
™osphewclerate increases in at-

‘tic radiation.

Does radiation produce
Yas armful genetic effects?
We animals: and plants, and
they take in human beings.
bat man € So long to show up
®d t) —'Y Senerations are requir-
So dy them.
at © ‘atom bomb stri
Stars ib. strikes -also
bongs! tity - We know that the
rit nog peed in Japan in 1945
des after © Senetic casualties
att a we are dead. But we
Out ay: i how many nor much
der Woulg HY will look like.
ide Miting €xpect certain bodily
“Oey, *S and a certain type of

aire there

dyed
Hon?
1 t

any other de-
effects of radia

hous} :
dig kno, 8h here again we don’t

€ enous
the is calleq on about them. A
8, od has
Oe) in Japanas a 1ré-
e bombs x

too many white
Is usually fatal,

Nine

. from
. Ute: ‘
is * exposure,

re likely where radio-

five to 40

take

“eukemia, in which

Tadiatj . F
Yeon tVthing 8 can cause can-. a member.

Strikes unseen

‘D. G. ARNOTT, secretary of the Atomic
Sciences Committee of the British Association —

of Scientific Workers, answers questions
submitted by MALCOLM MacEWEN

active dust has been swallowed
and has lodged in, for example,
the lungs and the bones, caus-
ing a heavy local overdose. This
may happen to some of the Jap-
anese fishermen who were delug-
ed with radioactive dust a year

ago.

* Is there any way of pre-

venting these effects,
either before or after
explosion?

N° practical processes exist, ex-
cept, of course, not to explode
the bombs.

% What do you think of
Sir Winston Church-
ill’s statements on the
danger of radiation in
the atmosphere result-
ing from hydrogen bomb
tests?

HE has been asked many ques-
tions about it and his replies

SCIENCE

By JOHN STACHEL

4uO science can go farther than
' the tools it has. available will
it. The greatest genius
could not have discovered atomic

‘energy without the radio tubes,

the electric circuits, the spectro-
scopes, the atom smashers that
give man mastery in the atomic
domain. That is why the use of
some new instrument or group
of instruments can mark the be-
ginning of a scientific revolution.

The invention of the micro-
scope in the 17th Century start-
ed such a revolution in biology.
But the study of lenses and the
properties of light that enabled
the microscope to be built was
not inspired iby research in bi-
ology, but by work in the sei-
ences of astronomy and naviga-
tion. :

It was a ¢ase of -one rapidly
developing science cross-fertiliz-
ing another.

Just such a scientific revolu-
tion is going on today in astron-
omy, in the years since the Sec-
ond World War. j

xt % mm

In 1931, J. G. Jansky, an Am-
erican radio engineer, had made
the startling discovery that a
very tiny part of the static heard
on sénsitive radio sets was com-
ing from the Milky Way, the
huge band of stars ‘visible in the
night sky, of. which our sun is

This meant that radio waves

from outer space were reaching
earth. Let me hasten to add

‘

have been either evasive or com-
placent.

I do not think that is a very
responsible attitude to take when
so many people are worried and
when scientists as distinguished
as Lord Adrian have warned
about the danger. : =

* Can you comment on
Churchill’s statement
that the total dose re-
ceived by the U.S. pop-
ulation from all nuclear
weapons is equivalent

to one chest X-ray?

HE was quoting from a mislead-

ing report of the U.S. Atomic

Energy Commission, which I have :

read in full. A chest X-ray is
about ten timés greater than the

figure quoted in the report.

A chest X-ray cannot be com-
pared with nuclear bomb radia-
tion, which is received over the

i, the safety é eee
Au Be wa enters, Radi re] m essages

that. they were not coming from
other living creatures. (Although
of course it is always possible
that a tiny fraction of them do.)

Any changing electric field
will send out radio waves,
whether man-made or not. But
just what heavenly objects were
responsible was impossible to de-
termine at that time, because
equipment to accurately detect
such feeble waves, measure them
and find from what direction
they came, was not available.
They could not be “tuned in”
accurately.

The big break for the develop-
ment of radio astronomy came
from quite another field, how-
ever. :

It was the feverish work done
before and during the war to per-
fect radar, which uses radio
waves to spot distant targets. In
order to get radar to work, Brit-
ish and American scientists had
to build a number of new instru-
ments to produce radio waves of
short and exactly determined
wave lengths, as well as other in-
struments to detect such waves,
even when they were very weak.

When the war ended, a num-
ber of scientists started using the
newly available radio equipment
to follow up Jansky’s work of 25
years before. ;

The basic tool they have de-
veloped is. the radio telescope.
Its basic structure is very simi-
lar to the ordinary telescope.

In an ordinary telescope light
from the stars is collected, mag-

nified by mirrors or. lenses, and

whole body, not just the chest.

Also, the bombs produce radio-
active dust which may be swal-
iowed, and produce illness after
many years. X-ray machines do
not do that.

Finally, nuclear bomb radio-
activity is not distributed uni-
formly over a country. Some
places will get more than others.
So I do not think the compari-

son with a chest X-ray is justi-
fied. 4

* Is an H-bowb test “‘holi-
day” feasible?
Vs but it must cover atom
bombs as well. If Britain took
the lead I believe the European
and neutral nations would sup

port it. So would Russia. And
there is widespread popular sup-
port for the idea in America.
There are even signs that the

U.S. government is worried about
the unpopularity of its tests.

from the stars

recorded either by the human
eye or a camera.

A radio telescope collects the
radio waves from space by means

of a huge aerial; the tiny electri-:

cal current produced by the
waves is then amplified by elec-.
trical equipment and recorded
either by watching it on a tele-
vision tube or using it to drive
an electric pen.
$e $e3 x

Even though it is an infant
science, radio astronomy already
has a number of notable achieve-
ments to its credit, and has
drawn attention to several new
problems in exploring the uni-
verse.

Radio maps of the skies have
been compiled, which already
list'several hundred spots in the
skies which emit strong enough
radio waves to be called radio
stars. These radio star areas do
not coincide with the places
where the brightest visible stars
are, so clearly they are drawing
our attention to something new,

Scientists are just beginriing
to be able to figure out what
these new things are.

For example, one very strong
radio star. is in a region of space
which shows nothing in an ordi-
nary telescope. But a look back

. into the records of the past

shows that this is just the spot
where Tycho Brahe, a great as-
tronomer, recorded a supernova
in 1572 — that is the explosion
of a star. What the radio tele-
scope picks up is the after-re-
mains of a dead star.

The two most powerful radio
stars in the heavens seem to re-
sult from the collision of two
galaxies — a cosmic accident in-
volving two huge island uni-
verses, each containing billions
of stars.

- dt is not yet known just how
the radio waves are emitted
from the radio stars, but clearly
the colossal explosions produced
by the collision of galaxies as in
the two cases studied would re-
lease huge amounts of energy
that somehow generated the
waves.

Our Own sun is a.radio star,
although not one of the strong-
est. But a study of its radio
waves has already. led to new
knowledge about the sun's at-
mosphere. ;

A _close connection between
certain types of solar radio
wave; and sunspot variations
and other magnetic storms on
the sun has also been found.

This may well lead to better
weather predictions in the future
if the connection between the
sun and our weather is as close
as Many weather experts believe.

All the known radio stars are
responsible for only a small part
of the cosmic radio waves reach-
ing earth, so we can expect many
new surprises from radio aston-
omy. Some scientists think that
there are actually about as many
radio stars as visible ones. That’s
why more and more of them, are
oe in on the universe alltthe
ime.

PACIFIC TRIBUNE — APRIL 15, 1955 — PAGE 9